Add 54/70 and 42/72, Solve 54/70 + 42/72 as a fraction

Add 54/70 and 42/72

54/70 + 42/72 is 569/420.

Find the least common denominator or LCM of the two denominators:
LCM of 70 and 72 is 2520

Next, find the equivalent fraction of both fractional numbers with denominator 2520
For the 1st fraction, since 70 × 36 = 2520,
54/70 = 54 × 36/70 × 36 = 1944/2520
Likewise, for the 2nd fraction, since 72 × 35 = 2520,
42/72 = 42 × 35/72 × 35 = 1470/2520
Add the two like fractions:
1944/2520 + 1470/2520 = 1944 + 1470/2520 = 3414/2520
3414/2520 simplified gives 569/420
So, 54/70 + 42/72 = 569/420
In mixed form: 1149/420

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